Our verdict is Uncertain significance. Variant got 0 ACMG points: 2P and 2B. PM2BP4_Moderate
The NM_002161.6(IARS1):c.3707-4C>A variant causes a splice region, splice polypyrimidine tract, intron change involving the alteration of a non-conserved nucleotide. The variant allele was found at a frequency of 0.0000588 in 1,581,498 control chromosomes in the GnomAD database, with no homozygous occurrence. In-silico tool predicts a benign outcome for this variant. 3/3 splice prediction tools predict no significant impact on normal splicing. Variant has been reported in ClinVar as Uncertain significance (★).
IARS1 (HGNC:5330): (isoleucyl-tRNA synthetase 1) Aminoacyl-tRNA synthetases catalyze the aminoacylation of tRNA by their cognate amino acid. Because of their central role in linking amino acids with nucleotide triplets contained in tRNAS, aminoacyl-tRNA synthetases are thought to be among the first proteins that appeared in evolution. Isoleucine-tRNA synthetase belongs to the class-I aminoacyl-tRNA synthetase family and has been identified as a target of autoantibodies in the autoimmune disease polymyositis/dermatomyositis. Alternatively spliced transcript variants have been found. [provided by RefSeq, Nov 2012]
Uncertain significance, criteria provided, single submitter
clinical testing
Ambry Genetics
Nov 12, 2020
The c.3707-4C>A intronic alteration results from a C to A substitution 4 nucleotides before coding exon 34 of the IARS gene. Based on data from the Genome Aggregation Database (gnomAD) database, the IARS c.3707-4C>A alteration was observed in 0.01% (27/282,220) of total alleles studied, with a frequency of 0.03% (8/25,110) in the European (Finnish) subpopulation. This nucleotide position is not well conserved in available vertebrate species. In silico splice site analysis predicts that this alteration will not have any significant effect on splicing. Based on insufficient or conflicting evidence, the clinical significance of this alteration remains unclear. -